Braking apparatus



Oct. 10, 1933. s. SCHNELL BRAKING APPARATUS Filed Sept. 23, 1931 "all.

Inventor STEVE SCHNELL Att'y.

Patented Oct. 10, 1933 UNITED STATES BRAKING APPARATUS Steve Schnell, St. Louis,

Electric Corporation, ration of Delaware Mo., assignmto Wagner St. Louis, Mo., a corpo- Application September 23, 1931 Serial No. 564,527

4 Claims.

My invention relates to hydraulic braking apparatus and especially to improvements in the construction of wheel cylinders therefor. Heretofore wheel cylinders for hydraulic brake sys tems have been made by first casting them from suitable material and then machining them to the proper form and dimensions, and it is the primary object of my invention to produce a satisfactory wheel cylinder which can be manufactured at much lower cost.

Other objects will become apparent from the following description of a preferred embodiment of my invention taken in connection with the accompanying drawing in which Figure 1 is a side view, partly in section, of my improved wheel cylinder installed in a brake; Figure 2 is a top plan view of the wheel cylinder and its support; Figure 3 is a cross sectional view'onthe line 33 of Figure 1; Figure 4 is a view of the mounting plate; Figure 5 is a cross sectional view of the stock steel from which the cylinder is produced; and Figure 6 is a cross sectional view of the bleeder valve.

Referring to the drawing in detail, 1 indicates a piece of stock steel rolled to a section as shown, one side being provided with a fiat surface 2 while the opposite side is provided with a curved surface. Stock of this kind is cut to the proper length and bored to provide a hollow cylinder 3 with relatively thin walls l. The external surface of each end 5 of the cylinder is machined to a radius equal to the radius of the cylinder bore plus the thicknessoi the wall of the cylinder and provided with an external cir- 5 cumferential groove 6.

, the fiat surface 2 of the cylinder by welds 12.

Small orifices 13 and 14 are bored through the part of the wall of the cylinder having the fiat exterior surface in alignment with the openings l and 11 in the mounting plate. The outer end of the orifice 13 provides a seat for a bleeder valve 15 which is adapted to be screwed into the opening 11 of the mounting plate. This bleeder valve is of the usual type having a central opening 16 communicating with a cross opening 17 just above the cone-shaped tip that abuts against the seat of the orifice when the valve is seated.

A conduit 18, connected with a suitable source of pressure is engaged by a threaded fitting 19 adapted to be screwed into the opening 10 of m the backing late. A copper gasket 20, or other suitable seal, is interposed between the end of the fitting and the fiat surface of the cylinder surrounding the orifice 14. It is thus seen that as the fitting 19 is screwed down against the gasket, there results a fluid-tight joint between the orifice 14 and the fitting 19. Since both the bleeder valve and fitting are in tight engagement with the surface 2 of the cylinder there is no necessity for having the welds 12 m produce a seal between the mounting plate and the cylinder and, therefore, the welds need only be strong enough to withstand the tension produced by the bleeder valve and the fitting when screwed into clamping engagement with the cylinder.

The backing or dust plate 21, which encloses the open side or the brake drum 22, is provided with a pair of openings 23 and 24 for the reception of a pair of screws 25 and 26 cooperat- W ing with the screw-threaded openings 8 and 9 of the mounting plate for securing the cylinder in its proper position. The backing plate is also provided with a pair of openings 27 and 28 for the passage of the bleeder valve 9 and the con- 85 duit fitting 19.

It is to be noted that the threaded openings and 1. in the mounting plate are of the same size, as also are the orifices 13 and 14 of the cylinder. The bleeder valve and the conduit fitting 19 may, therefore, be interchanged from the positions shown if any special location of the cylinder, or parts of the vehicle, or braking system, or special form of backing plate made this desirable. This construction also facilitates 95 assembly of the cylinder to the backing plate as it is not necessary at that time to consider whether the bleeder valve or conduit fitting have to be placed in the upper or lower opening in the mounting plate.

The bore of the cylinder is fitted with a pair of oppositely moving pistons 29 and 30 and cup washers 31 and 32 to prevent leakage. These pistons are also preferably made from a cold rolled steel rod although pistons of other rnal05 terial may be used. The outer ends of the pistons have cut out sockets for the reception of the pins 33 and 34 operatively connected to the brake shoes 35 and 36. Rubber dust boots 37 and 38 tightly surround and support the pins 3 3 and 34 no and are secured to the ends of the cylinder 3 by means of the previously mentioned circumferential grooves 6.

. From the above description it will be seen that I have produced a steel wheel cylinder from ordinary stock steel that is very cheap and light in weight and one which can be manufactured by inexpensive operations,drill and punch presses and a welding machine being all the machinery required.

Having fully described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. A cylinder having a fluid passage through its wall, a mounting plate secured to the cylinder and provided with an opening aligned with saidfluid passage, a fluid conduit element extending through said plate opening, and means coacting with the plate for clamping the end of the conduit against'the cylinder surfacesurrounding the fluid passage with sufficient pressure to maintain a fluid-tight joint between said-conduit element and the cylinder.

2. A. cylinder having a fluid supply opening through its wall, a mounting plate secured to the cylinder and provided with an opening of larger diameter than said fluid supply opening and aligned therewith, and a fluid conduit element threaded in said plate opening and in fluid tight relation with the cylinder surface surrounding the fluid supply opening.

3. The combination of a cylinder provided with an external flat surface and a fluid supply opening through the wall thereof, a mounting plate overlying the flat surface of the cylinder and provided with an opening in alignment with said supply opening, and fluid conducting means extending through the plate opening and in threaded engagement with the wall thereof and having its end maintained in fluid-tight pressure engagement with the cylinder surface surrounding the supply opening by the threaded engagement.

4. In a fluid motor, a cylinder provided with a flat external surface and with a pair of fluid openings through the wall thereof, a mounting plate overlying and secured to the flat surface of said cylinder and provided with two openings each in alignment with a cylinder fluid opening, a fluid supply conduit element extending through one. of the openings in the plate, means coacting with the plate for maintaining the end of the element in fluid-tight engagement with the surface surrounding one of the fluid openings into the cylinder, and a valve member screwed into the other opening in the plate and adapted to close the other fluid opening into the cylinder.

STEVE SCHNELL. 

